Coloring system for leather finishing



J. G. PENNIMAN, JR 3,424,300

COLORING SYSTEM FOR LEATHER FINISHING Janes, 1969 Filed March 8. 1966 (I4-mams 'ma lo davGNv1S=sl INVENTOR. JOHN G. PENNIMAN,JR.

ATTORNEY United States Patent COLORING SYSTEM FOR LEATHER FINISHING John G. Penniman, Jr., Pleasantville, N.Y., assignor to Penniman Chemicals, Inc., Pleasantville, N.Y., a corporation of New York Filed Mar. 8, 1966, Ser. No. 532,733

U.S. Cl. 206--47 lut. Cl. B65d 79/00, 85 70; A45c 11 00 Claims thereon of the color desired such as to match the various wardrobe colors of the consumer.

The ter-m leather las used herein includes synthetic as well as natural leather. For convenience, the term color is used to include black and white or combinations thereof as well as the varous hue colors while the term hue color excludes black and white or combinations thereof.

The invention broadly -relates to a series of pods or sealed plastic envelopes each containing a leather finishing composition comprising a film -forming resin and a pigment to impart to the compositions contained in the pods the var-ious -colors desired. The invention includes a separate series of pods for each hue color of variable hue pigment Istrength or pigment volume concentration (PVC), ranging from full strength or standard strength to a strength of about one-one hundred-twenty eighth. The pods of less than full strength hue color pigment advantageously contain a suflicient amount of a nonopaque extender pigment to bring the total pigment volume concentration up to about the PVC of the standard strength pod.

FIG. 1 illustrates a plastic pod into which a leather finishing composition has been sealed. The leather finishing composition can be removed therefrom by simply cutting or tearing off one corner of the pod such as shown by the cut line in the drawing. Any Asu-itable packaging material, such as polyethylene 4or Mylar film or aluminum foil, can be used Ifor containing the compositions and the pod sealed in any manner desired.

FIG. 2 of the drawing schematically illustrates one system by which the invention can be practiced. The blocks in the diagram illustrate a group of individual pods each containing 1A liu-id ounce of pigmented nishing composition. Each pod contains substantially the same 4amount of an acrylic copolymer film forming resin or adhesive having abou-t 46% solids. The group of pods are divided into sub-groups for each hue color used in the system namely, red, orange, brown, yellow, green, blue and violet. The pods marked S in each sub-group in the first line are the standard or full strength -pigmented compositions each `containing an amount of 4the particular color pigment indicated on the chart to give the optimum or desired color and opacity for the particular pigment used. The numbers in the following seven lines of each sub-group indicate the amount of color pigment present in each pod based on the amount present in the standard. In this particular system, there are only three pods containing the white pigment; one of standard strength, namely 28% PVC; one of 1/2 standard strength, and one of 1A standard stren-gth. The pods containing the black pigment ranges from a standard strength of 2.2% PVC through to a strength of 1/128 of the standard.

The compositions in the pods contain-ing less than the standard or full strength amount of pigment also adrice vantageously contain a non-opaque extender pigment such as clay in a sufiicient amount to bring the total pigment volume concentration ('PVC) of each such composition to approximately equal to the PVC of the standard composition. Thus if a standard green pod was prepared using a PVC of 21% a 1/2 strength green pod would be prepared by adding only 1/2 of the standard amount of pigment to the film forming resin emulsion to give a color pigment PVC of lOl/2% and a sufcient amount of an inert non-opaque extender pigment such as clay added thereto to give a ytotal PVC of about 21%.

In the particular system depicted in FIG. 2, the standard black composition or pod contains carbon black at a PVC of 2.6% and no non-opaque extender pigment. The use of the low PVC for black is advantageous yfor this system to prevent drowning out of the other colors or -mixtures thereof due to the high hiding power of carbon black. The pods containing black pigments of less than standard strength from 1/2 to 1/128, as shown in the drawing, contain a non-opaque extender pigment, nalmely clay, in a sufficient amount to bring the total PVC up to the standard PVC strength of about 2.6%. The standard black pod containing no clay or other nonopaque extender pigment is advantageous in this particular system to retain jetness. The black pods of less than full strength containing the extender clay pigment are not used primarily for jetness, but as :a tinting medium. A single standard black pod could be used if desired, but the use of pods of less than full strength as indicated is advantageous.

Since the standard black pod as well as those of reduced strength has a PVC of only about 2.6%, a reduction to total PVC will occur when one or more black pods are used to produce the desired color by this four pod system. Although this reduction in total PVC will affect the fil-m properties somewhat, the retention of the black jetness of the standard and tinting quality of the reduced strength pods is considered to outweigh any lm deficiencies that might occur.

The white standard pod contains titanium dioxide pigment `at a PVC of about 28% and no non-opaque extender pigment. The two pods containing 1/2 and 1A standard strength pigment contain a suicient amount of clay extender pigment to bring the total PVC to approximately that of the standard pod.

The grey standard pod in this particular system is a mixture of a standard white and a standard black composition on a one to one ratio and the total volume of course reduced to 1A: ounce for each pod. The pods of reduced pigment strength are in the standard black to standard white ratios indicated in FIG. 2. No non-opaque extender pigment is used in this system with the grey pods.

The system shown in FIG. 2 contains only one standard strength pod of white and black and no pods of less than standard pigment strength simply because they are not necessary to produce the desired number of colors by this particular system.

The particular hue color pigments and the PVCs thereof for the standard pods used in the system shown in FIG. 2 are as follows:

The grey or color pigment PVC of the reduced strength 3 pods can readily be calculated as described herein and shown in FIG. 2.

In practicing the invention a swatch book is prepared by Iblending the contents of the pods of various colors and strengths and coating these colors on an appropriatel base, preferably leather or paper, to form swatches of all of the combinations desired. These swatches are placed in a book and the particular pods used to make the colors and shades indicated. The swatch book may contain in excess of 5,000 different colors and shades.

The user then simply selects the desired color or shade from the swatch book yand picks out the pods as directed by the swatch book. The pods are then cut and the contents placed and mixed in a suitable container such as a spraygun bottle. The leather finishing composition is then ready for immediate application to a leather article such as a pair of womans shoes.

An example of one of the numerous colors or shades which can be produced using the particular system described and applied to a leather Iarticle would be one 1A ounce green pod of 1/2 strength, one 1/4 ounce blue pod of 1/{52 strength, one 1/4 ounce white pod (full strength), and one 1A ounce pod of black (2.6 PVC). Each pod is cut and the contents mixed in a spraygun `bottle and sprayed on a pair of womans leather shoes to a thickness of about 0.4 mil and permitted to `air dry. The green coating is then covered by a conventional clear lacquer film as described in my copending ap-plication referred to herein and permitted to air dry to give a more glossy appearance to the finish.

The particular system illustrated in FIG. 2 is a four pod system in that each color from the swatch book would require a combination of four pods. Since each pod contains 1A uid ounce the leather finishing composition when mixed would total one fluid ounce. This amount of composition is generally sufficient to finish most leather wardrobe articles such as Ia pair of shoes or a handbag.

The leather finishing compositions of any desired color can thus be easily prepared with no expensive equipment, with little or no skill required, and with complete confidence of preparing the exact color leather finish desired. The volume of the mixed finishing composition is controlled thus reducing waste. The solids contents are also controlled giving uniformity to the finishes. The finishing compositions are stable and can be stored for long periods of time without change in volume or color. Premature drying or scum formation is also avoided. The invention further provides a method of finishing leather articles in any desired color in a retail store, a fabricating factory or other location apart from the tannery.

The basic film forming resin, or adhesive, into which the various color pigments can be incorporated or formulated is preferably an aqueous acrylic polymer emulsion as described in my copending United State application, Ser. No. 472,028, filed July 14, 1965. The acrylate ester emulsion as described therein is one which has a glass transition temperature of less than about 50 F., a pH of more than about 7, a polymer particle size of less than about 0.3 micron, a viscosity of less than about 100,000 cps. at 25 C. and a free monomer content of less than about 0.5% by weight. The polymer is preferably a terpolymer of lower alkyl acrylic esters, such as a butyl acrylate, methyl methacrylate, and ethyl acrylate. Although the above film forming resin or binder is particularly advantageous in practicing the present invention, the invention is not dependent thereon, and any film forming resin or binder can be used so long as it can form a pigmented composition capable of being readily applied to a leather surface and have the necessary pigmented film properties for use on leather goods such as adhesion, abrasion resistance, flexibility, and so forth.

The percentage solids of the resin binder in its aqueous medium can vary as will be appreciated by those skilled in the art. It is only necessary to have suiiicient solids to produce a pigmented film having the properties desired as previously discussed.

Various pigments, or combinations thereof, can be incorporated into the resin binder and used according to this invention to impart the various colors desired, to the compositions as will ybe understood by those skilled in the art. In order to obtain the most desired number of color shades, it is advantageous to employ the hue colors, red, orange, yellow, green, blue, brown, and violet, in full or standard strengths and in a series of reduced strengths as described herein. Examples of pigments which can be advantageously used, according to this invention, include quinacridone red, molybdate orange, chrome yellow, phthalocyanine green, burnt umber, phthalocyanine blue, and quinacridone violet. The brown pigment of the desired shade for the standard strength as well as reduced strengths can also be prepared by mixing yellow, black and red pigments or other brown pigments, such as Sirius Supra-Brown RD can `be used. It is also preferred to use titanium dioxide for white and carbon black for `black and a combination of these for grey. Many other well-known pigments or coloring agents can be used to impart the desired color or shade, as will be understood by those skilled in the art.

In practicing the invention, a standard resin emulsion of predetermined solids content is first selected which is capable of giving the desired pigmented film properties on a leather article. An example 0f such a standard emulsion is one which contains an acrylate polymer of about 79.5% by weight, ethyl acrylate; 19.5% by weight methyl methacrylate; and 1% by weight itaconic acid, and having a solids content of about 46%. The particular pigment selected is then added to this resin emulsion in a Sufficient amount to obtain the desired color, shade and opacity to form a full strength or standard leather finishing composition `which can be placed and sealed into plastic pods. With most pigments, it is desirable to incorporate into the resin emulsion, the highest concentration practical to form the full strength or standard pod. The practical limit on the amount of pigment which can be used is determined by the resulting physical properties of the pigmented film or coating. It is quite apparent that as more and more pigment is added to the resin emulsion, the film properties will be altered until a point is reached where the desired film properties will begin to fall off. Thus the amount of pigment used should Ibe limited to that amount which will not significantly impair the film properties desired, such as adhesion, abrasion resistance, scutf resistance, and so forth, as discussed above.

Generally, the highest practical concentration of pigment which can be used is a pigment volume concentration (PVC) of about 30%. The optimum PVC of the hue colors generally varies between about 20 and 30% depending upon the particular pigment selected to obtain optimum color and opacity, as well as optimum film properties for the standard or full strength pods. The general PVC maximum of about 30% also applies t0 white. Black is an exception because the carbon black used has exceptionally high hiding power, and it is generally advisable to formulate the full strength or standard black pod with a PVC of about 3%. This very low PVC for black permits the invention to operate more easily in a four-pod system. If a 30% PVC standard black 1A ounce pod were used, and mixed with three other pods of various hue `colors or white, the black would tend to drown out the other colors.

A standard or full strength pod is one which contains a color pigment in the range of or under the critical or maximum PVC for the particular color pigment and resin being used. The maximum color pigment PVC which is used is dependent mainly upon the particular pigment being employed and the particular color system being designed. Where the pigment being used is exceptionally strong or has exceptional hiding power, it may be used, it may be used in an amount less than its highest possible percentage insofar as optimum film properties are concerned where the necessary percentage produces the optimumI color and opacity desired. Thus, the standard or full strength pod is one which contains the highest PVC Ifor any one group of color pigmented pods.

The particular ygreen and brown pigments, namely phthalocyanine green and burnt umber, are examples of pigments which are most advantageously used at less than the maximum or critical PVC, since the optimum color and opacity are obtained at lower PVCs for the particular system described herein.

Once each standard composition has been formulated, compositions or pods of lesser strength can be readily prepared by reducing the amounts of various hue colors to one-half strength, one-fourth strength, and so forth, to the extent desired for any particular system.

The reduction of the amount of pigment to form the composition or pod of less than full strength would alter the physical properties of the resulting lm. The amount of pigment left out in forming the composition or pod of less than full is therefore advantageously replaced by a non-opaque extender pigment. Thus if the standard or full strength composition or pod is prepared using molybdate orange at 28% PVC, a pod of one-half full or standard strength would be prepared using molylbdate orange at 14% PVC and a non-opaque extender pigment, such as clay added thereto to bring the total PVC up to about 28%. If a full strength green composition or pod was prepared using phthalocyanine green at a PVC of 2l, a one-half strength green would be prepared by adding the green pigment to a PVC of 101/2 and adding thereto a non-opaque extender pigment to bring the PVC up to the standard for the particular color, namely a PVC of about 21%. Thus in practicing the invention, the mixing of four pods of one ounce each together results inconsistent film properties.

Various non-opaque extender pigments can lbe used in practicing this invention, such as mica, clay, talc, and calcium carbonate. Clay is most advantageous. The use of the non-opaque extender pigment as a replacement for the hue pigments in formulating the pods of less than :full strength is very advantageous in that it maintains the consistency of the compositions of the various hue colors at their various strengths and also maintains substantially consistent physical properties of the films after they have been applied and dried. The use of a non-opaque extender pigment also produces Iconsistency in the colors of the various compositions or pods of less than full strength. This combination of features obtained by using the nonopaque extender pigment allows for the formation of 5,000 or 4more different shades or colors by using only eight pods of various strengths for each of the colors used in the system. Virtually, any color of the customers wardrobe lcan therefore be matched using up to eight of the various Astrengths for each hue color in the system.

It is also advantageous to maintain a fairly uniform solids content of the resin emulsion throughout the system. The particular resin emulsion solids content is not critical so long as the solids content is fairly consistent throughout -any one particular system. Variation in the solids content of the resin emulsion will also `alter the PVC of the compositions used to prepare the standard pods as will be apparent to those skilled in the art.

Various other ingredients can be incorporated into the leather finishing compositions placed in the pods as will .be understood by those skilled in the art. Ingredients such as stabilizers and emulsifying Iagents generally used in the resin binder emulsion can be present as well as resin stabilizers and emulsifyng agents for obtaining good pigment dispersions therein. Examples of such ingredients are given in my copending application referred to above. The only limitation with respect to such additional ingredientes would |be that they would not interfere significantly with obtaining the desired color or opacity or physical properties of the resulting film.

The pigments are incorporated into the resin emulsions in the conventional manner as will be understood by those skilled in the art. The pigment is thus preferalbly ground and formed into a slurry prior to the addition of the resin emulsion.

Many different embodiments, besides that specifically illustrated in BIG. 2, can readily be developed and practiced according to the invention as will be apparent to those skilled in the art. For example, the number of hue colors as well as the number of reduced strength pods can be varied quite Widely depending upon the number of colors or shades desired. Obviously, as the number of color pods are reduced, the number of possilble color combinations is correspondingly reduced and vice versa. The invention oould be practiced, for example, by using compositions or pods containing only those pods up to 3&2 color pigment strength or the grey or brown colors eliminated altogether. A neutral pod containing only a nonopaque extender pigment could also be used if desired. A certain amount of opaque extender pigments could also be used in finishing compositions so long as they 'would unduly interfere with the range and type of colors and shades desired. Thus, the particular system shown in the drawing is by way of illustration only `and represents the best mode known to date.

The color pigment PVCs can be reduced to various percentages of :the full strength or standard PVCs in other manners than those described. For example, the color pigment PVC can be reduced by adding additional latex, but this has the disadvantage of altering. the pigment volume concentration.

Pods can also be incorporated in the system of this invention which contain various hue colors of various strengths and also other hue color or white pigments. For example, a Mt strength red composition might be prepared and sufficient white pigment, such as titanium dioxide, incorporated therein to bring the total PVC up toapproximately that of the standard red pod, thus eliminating the use of non-opaque extender pigments. The use of a white opaque pigment with various reduced strength color pigments is advantageous in obtaining a wider range of pastel colors. In some cases, one or more diterent hue color pigments can be Aused in combination with both -a white opaque pigment and a non-opaque extender pigment. The pods of less than full strength could `also contain color pigments of various fractions of the standard pods and need not be of the particular fractions indicated in the drawing.

It is also quite apparent that the invention can be practiced using different systems. A three or dive pod system could be developed for example, and the fluid content of any of these systems including the four pod system altered as may be desired to obtain the desired end quantity. Finishes could also be formulated from the four pod system using less than or more than four pods, but this would result in a change in end volume of the finish.

I claim:

1. A balanced color system particularly suitable for nishiing light or white synthetic or neutral leather in a variety of colors and shades comprising:

(a) a group of sealed pods each containing approximately equal volumes of hue color pigmented coating compositions, said :group of pods including subgroups of pods for each hue color pigment employed in the system and each sub-group comprising a pod containing a hue color pigmented coating composition of standard pigment concentration and a series of additional pods containing the same hue color pigment of variable pigment concentration less than the pigment concentration of the standard pod, and

(b) a pod containing a black pigmented coating composition and a pod containing a `white pigmented coating composition, each containing approximately the same volume as the group of hue color pigmented pods.

2. The color system of claim 1 in which the pods containing less hue color pigment than the standard pod also contain a sufficient amount of a non-opaque e-xtender pigment to bring the total pigment concentration up to about the same concentration as the standard pigment pod.

3. The color system of claim 2 having at least 6 subgroups of hue colors including red, orange, yellow, green, blue and violet in which the pods containing less hue color pigment concentration than the standard pods have hue color concentrations ranging from 1/2 to 1/128 of the standard pods and the black pigmented pod contains about 3% pigment volume concentration.

=4. The coloring system of claim 1 in which each pod contains approximately 1A fluid ounce and each color is obtained by blending together the contents of four pods.

5. A method of coating goods such as leather and synthetic leather in a variety of colors and shades in which the coating can be applied to the goods at the retail level, which coimprises (a) providing a group of sealed pods, each containing approximately equal volumes of hue color pigmented adhesive resinous compositions, and in which the group of pods includes subgroups of pods for each hue color pigment employed; each subgroup comprising a pod containing a hue color pigmented adhesive resinous composition of standard pigment concentration and a series of additional pods containing the same hue color pigment of variable pigment concentration less than the hue color pigment concentration of the standard pod and (b) a pod containing a black pigmented adhesive resinous composition and a pod containing a white pigmented adhesive resinous composition and each containing approximately the same volume as the group of hue color pigmented pods, mixing a plurality of contents of the pods together to produce a predetermined desired color of substantially constant volume, and applying the resulting mixture to the goods.

References Cited UNITED STATES PATENTS 1,360,085 11/1920 Bradley 206-46 1,957,816 5/1934 Braeg 206-1.7 2,830,396 4/1958 Gowland 206-1.7

JAMES B. MARBERT, Primary Examiner.

U.S. Cl. X.R.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION January 28, 1969 Patent No. 3,424,300

John G. Penniman, Jr.

It is certified that error appears in the above identified are hereby corrected as 'patent and that said Letters Patent shown below:

Column 6, line 60, "neutral" should read natral Signed and sealed this 17th day of March 1970.

(SEAL) Attest:

Edward M. Fletcher, Jr. WILLIAM E. SCHUYLER, Commissioner of Patents Attesting Officer 

1. A BALANCED COLOR SYSTEM PARTICULARLY SUITABLE FOR FINISHING LIGHT OR WHITE SYNTHETIC OR NEUTRAL LEATHER IN A VARIETY OF COLORS AND SHADES COMPRISING: (A) A GROUP OF SEALED PODS EACH CONTAINING APPROXIMATELY EQUAL VOLUMES OF HUE COLOR PIGMENTED COATING COMPOSITIONS, SAID GROUP OF PODS INCLUDING SUBGROUPS OF PODS FOR EACH HUE COLOR PIGMENT EMPLOYED IN THE SYSTEM AND EACH SUB-GROUP COMPRISING A POD CONTAINING A HUE COLOR PIGMENTED COATING COMPOSITION OF STANDARD PIGMENT CONCENTRATION AND A SERIES OF ADDITIONAL PODS CONTAINING THE SAME HUE COLOR PIGMENT OF VARIABLE PIGMENT CONCENTRATION LESS THAN THE PIGMENT CONCENTRATION OF THE STANDARD POD, AND (B) A POD CONTAINING A BLACK PIGMENTED COATING COMPOSITION AND A POD CONTAINING A WHITHE PIGMENTED COATING COMPOSITION, EACH CONTAINING APPROXIMATELY THE SAME VOLUME AS THE GROUP OF HUE COLOR PIGMENTED PODS. 